February '08 | "Where is the scientific evidence?"
A summary of the scientific “references concerning human and animal toxicological/health risks studies on GM foods” during the current decade has recently been updated. The list, published at the end of 2007, barely runs to one and a half pages.
The review was compiled using the Medline electronic database of scientific publications. Its author noted that while there was “a considerable number of commentaries, general news and letters to the editor in reputable international journals, papers about experimental investigations on the safety of GM foods were surprisingly very scant”.
Out of at least 4,127 citations on aspects of “transgenic foods”, only 2-3% mentioned “toxicity” or “health risks”, and of these less than one quarter described actual feeding studies.
A total of 29 papers were unearthed which described feeding studies involving 37 separate groups of experimental of animals. Of these, four can be excluded because the animals used were irrelevant to human physiology (they were fish, birds and ruminants) and four did not appear to include any actual toxicity assessment. This leaves 29 published safety experiments on GM (amounting to less than 1% of the citations on GM foods) .
The GM material tested in these 29 experiments seems to include at least 15 different genetic transformation events in 9 different plant species.
No established protocol seems to be followed for the identification of toxic effects in the experiments. The organ systems examined vary widely, the length of time of feeding GM ranges from 10 days to 5 months (two-thirds were shorter than the standard 90-day feeding trial), and only two studies covered possible reproductive effects.
About one fifth of the experiments gave indications of pathological symptoms: none of these have been repeated.
The paper ends with a question: “where is the scientific evidence showing that GM plants/food are toxicologically safe, as assumed by the biotechnology companies involved in commercial GM foods?”
In response to a letter drawing the Westminster Government's attention to this 'scant' collection of experiments on GM food safety, a letter from the Department of the Environment, Food and Rural Affairs (DEFRA) was forwarded which set out its position on GM foods:
DEFRA supports people being able to make an informed choice, but also supports choice for those who might want to use or consume GM
DEFRA is conforming to EU rules
the public is assured that ensuring safety is DEFRA's top priority, that it will only license GM crops if it is clear that there will not be human health effects, and that its position will be based on a careful assessment of the scientific evidence.
The Word Health Organisation (WHO) has indicated that “individual foods and their safety should be assessed on a case-by-case basis because “it is not possible to make general statements on the safety of all GM foods”, and that safety assessment of GM foods should investigate in particular “toxicity” and “any unintended effects which could result from the gene insertion” (2002).
The National Farmers Union (NFU) recently stated that “informed choice for both consumer and grower is pivotal in taking this technology forward. The NFU therefore calls for an intelligent, practical and science-based debate ...” One of its branch representatives said it was time “to revitalise that important debate”.
OUR COMMENT
To state the obvious, since science can only measure something once it has been identified, any unexpected effects will only be found by a wide-ranging examination of living organisms who have been exposed to GM food. This means looking at all the main organ systems of appropriate laboratory animals, followed by monitoring in humans. If questions are raised by any of these studies, repeat and follow-up experiments must be performed. Whatever testing has been carried out on GM foods, it has not been of publishable quality and has not been made available for scientific or public scrutiny.
How can DEFRA be 'clear' that GM foods 'will not affect human health', or make a 'careful scientific assessment' when the evidence is just not there?
How can people make an 'informed choice' when the evidence on which to base the choice is just not there?
How can we have an 'intelligent, practical and science-based debate' when the evidence is just not there?
Try drawing your own MPs attention to this latest review (details below). If we say it often enough, perhaps the government will notice that their words are not being backed up by hard facts.
SOURCES:
- J. L. Domingo, 2007, 'Toxicity Studies of Genetically Modified Plants: A Review of the Published Literature' in Critical Reviews in Food Science and Nutrition, 47 pp.721-33
- Farmers Guardian, 30.01.08
- Letter from DEFRA 10.01.08